A sub 400° C. Atomic Layer Deposition (ALD) process has been reported for growing monolayers of Si on clean surfaces by alternating pulses of Si2H6 and SiCl4 employed with the substrate temperature varied between 355°-385° C. The process is slow, with each ALD cycle taking several minutes and the desorption of the HCl(g) biproduct being slow below 400° C. Other processes include monolayer silicon ALD growth on Ge with use of alternating pulses of Si2Cl6 and atomic hydrogen, or Si2Cl6 and Si2H6, at undesirably high substrate temperatures of 400°-465° C. These processes, however, are not self-limiting.
Physical vapor deposition (PVD) of silicon for passivation of III-V surfaces has been reported, but requires a silicon multilayer as the silicon is not ordered. Also, the PVD deposition of silicon is not compatible with processing of three dimensional devices such as finFETs on large semiconductor wafers.
There is a need in the art to provide self-limiting and saturating silicon Chemical Vapor Deposition (CVD) and ALD on non-silicon surfaces.